Mohamed Mahmoud

Tunable fiber Bragg gratings modeling and simulation

Thermally tunable fiber Bragg gratings (FBGs) have been widely used in optical communication systems for wavelength tuning and dispersion compensation. To simulate the FBG thermal tuning process, a mathematical thermal tuning model has been developed, a stored heat energy Bragg wavelength mathematical relationship has been defined and the thermal tuning response time calculated.

Real-time data acquisition system for monitoring patients in an intensive care unit (ICU)

In Intensive Care Unit (ICU) patient’s physiological variables such as heart rate, blood pressure, temperature, ventilation and brain activity are constantly monitored on-line, and medicine doses are given to ensure that these variables remain within desired limits. Such data are vital not only for on-line but also for off-line analyses and for medical staff training. Furthermore, in cases of deceased patients it is very important to retrieve these data in order to investigate the causes of deaths. This paper is introducing a design of a Real-Time Data Acquisition System for monitoring patients in Intensive Care Unit (ICU). The proposed design is implemented on a standard personal computer (PC) and operating system without using any sophisticated hardware or interface devices.

Design of a fuzzy logic hydraulic turbine governor

In this article a fuzzy logic turbine governor is designed and simulated for the control of a hydraulic turbine, together with its penstock, based on a nonlinear turbine model. The designed fuzzy logic governor can be used in hydropower plants, and may replace the commonly used classical PID turbine governors that are causing instability problems.

Fiber optical artificial nose for the food industry

An artificial nose has been attractive for scientific research and the food industry. This paper proposes that the detection and recognition of odours or chemicals concentrate can be achieved by means of passive and compact size fiber optic sensors (Fiber Bragg Gratings Technology) that will form an olfactory sensor array and a fuzzy logic algorithm that will form the recognition artificial intelligence. The mathematical model of the fiber Bragg gratings olfactory sensor is developed and the design model of the artificial fiber optic nose is introduced.

Global Positioning System Time-Transfer Error Correction Using Neural Networks

Time-transfer is the process of using a GPS receiver to derive accurate time relative to GPS system time. The GPS receiver clock error establishes the relationship between the receiver’s time and the GPS system time. The main problem here is to estimate the desired range equivalent of receiver clock error. Kalman filter is one of the methods used to estimate the various error components separately using observations made over time. This paper proposes the use of neural networks for the estimation of these error components based on a revised time-transfer error model.

Real-time virtual fiber Bragg gratings

Fiber Bragg gratings (FBGs) have been widely used in optical communication systems for wavelength tuning and dispersion compensation. FBGs are made by laterally exposing the core of a single-mode fiber to a periodic pattern of intense ultraviolet light. This proposes that, by exposing the fiber core to other temporary and alternative exposure sources in real time may create a gratings effect which is so called “real time virtual gratings”. The virtual gratings can be classified as a real time adaptive fiber Bragg gratings which may be used in dispersion compensation applications.

Adaptive dispersion compensation devices for optical communication systems

Although tunable fiber Bragg gratings are flexible and promising solutions for dispersion compensation, but we still have the problems of variable optical communication path characteristics, environmental fluctuations and the variety of applications, that require re-design and fabrication of fiber Bragg gratings for each case. An alternative novel technique of dispersion compensation based on adaptive fiber Bragg gratings scheme would overcome these problems. In this paper three different real time adaptive dispersion compensation schemes, are introduced; scheme based on pulse shape detection, scheme based on crosscorrelation detection and scheme based on pattern recognition.